We have gotten a number of user complaints about colons being
parts of a word. This is only needed in Swedish and a couple of
other languages, and is unexpected outside of them. We propose
that colon (and its variants) be removed from MidLetter, and
that the CLDR committee instead add them in just the appropriate
languages. It would probably be best to have a PRI item for
this, and thus not target 6.2, but rather 6.2.1.